Can't unmount or delete RAM disk

I managed, somehow, to create a 1Mb ram disk and format it with the fat format. I also apparently mounted the drive B:\. I realized it was too small to be of much use, but when I try to unmount or delete the disk, I get the following error message: You cannot perform this operation on a disk currently mounted by another user. What can I do?

I get this problem now and then on Windows 8.1, and it prevents my ramdisk to be cleaned on fast shutdown (after I log on again, the temporary files are still in it). I suspect it's the Windows suspend function that causes it.

Hello, Andrew. I'm sorry for not giving more details before. As a workaround to this problem with Windows 8, I've removed these keys from the registry and set up a Windows task to launch SoftPerfect RamDisk. That way, I don't need to disable the hybrid boot, and my ramdisk is cleaned automatically every time I turn my computer off the standard Windows 8 way.

However, sometimes your software locks my ramdisk and I get the same error as the original poster of this thread. I've noticed that this usually happens when I use the suspend feature of Windows.